…they’ve developed a temporary electronic tattoo that can induce just enough sweat to get a highly accurate read—which would be sent to a smartphone with an easy-to-interpret app—in minutes.
Source: Temporary Tattoo Tells You When You’re Drunk
If this “tattoo”can detect blood alcohol what else could be detected with a similar process? Blood sugar, cholesterol, enzymes?
On the other hand there does seem to be a well established relationship between getting tattoos and being drunk.